A Practical and Efficient Green Synthesis of β-Aminophosphoryl Compounds via the Aza-Michael Reaction in Water

Abstract

Application of water as a solvent (without any cosolvent) promotes the aza-Michael reaction of diethyl vinylphosphonate and diphenylvinylphosphine oxide with a wide range of N-nucleophiles. The solubility of the starting phosphorus substrate in water does not play a crucial role in the reaction course, decreasing to some extent the reaction rate. The reaction can be performed either at room temperature or under reflux to afford the corresponding β-aminophosphonates and β-aminophosphine oxides in excellent yields and of high purity via a simple freeze-drying isolation procedure. Application of basic catalysts makes possible the addition of weak nucleophiles such as α-amino acids and their phosphorus analogues; that is, α-aminophosphonic acids. The aqueous aza-Michael reaction allowed us to easily perform double phosphorylation of primary amines including polyamines using a reactant ratio (phosphorus substrate: amine) of 2:1.

Keywords:

• β-Aminophosphoryl compounds
• aza-Michael reaction
• green chemistry
• nucleophilic addition
• phosphaalkenes
• water

Acknowledgments

This work was supported by the Program of Chemistry and Material Science Division of RAS and program of the president of the Russian Federation for young Ph.D. scientists (No. MK-425.2010.3).